What to do if my Fit shows the symbol for TPMS(Tire pressure monitoring system)?

Likely not calibrated properly after the new tires installed or sensors damaged during the process.

Who ever put the tires on needs to recalibrate the TPMS system.

Whoever changed the tires probably broke/damaged the sensors,honda tpms does not need 'recalibration' just for a tire change. Also if all four tires were low at the same time , that will turn the TPMS indicator on.Code would need to be cleared with a scanner that's compatible with Honda , but would not necessarily need re-calibration(or 'sensor ID learning').-----------------------------------this info is for people like me -----just now getting around to reading the question. A year to late for someone else, though.